John thompson



{No Model.) 2 SheetsSheet 1.

J. THOMPSON. GRINDING MILL.

No. 504,761. Patented Sept. 12, 1893.

awmmtoz wi/tmeowo 72/0 L i izmwfi e (No Model.) 2 SheetsSheet'2 J.THOMPSON.

GRINDING MILL Patented Sept. 12, 1893.

Wvtmaooeo UNITED STATES PATENT OFFICE.

JOHh. THOMPSON, OF BUOYRUS, OHIO, ASSIGNOR TO THE FREY-SHECKLER COMPANY,OF SAME PLACE. 7'

GRlNDlNG-MlLL.

SPECIFICATION forming part of Letters Patent No. 504,761, datedSeptember 12, 1893.

Application filed April 5, 1893.

To all whom it may concern:

Be it known that 1, JOHN THOMPSON, a citizen of the United States,residing at Bucyrus, in the county of Crawford and State of Ohio, haveinvented certain new and useful Improvements in Grinding-Mills; and I dohereby declare the following to be a full, clear, and exact descriptionof the invention, such as will enable others skilled in the art to whichit appertains to make and use the same, reference being had to theaccompanying drawings, and to the letters and figures of referencemarked thereon, which form a part of this specification.

Figure l, is a perspective view of a grinding mill embodying myinvention. Fig. 2, is a side elevation of the same. Fig. 3, is aperspective view of the corrugated feed board and its adjuncts.

My invention relates to grinding mills of the class employing crushingrolls and generally known as roller mills, and my invention consists ofthe constructions and combinations of parts hereinafter fully describedand claimed.

In the drawings I disclose a well known I form of machine to which Ihave applied my invention, and wherein a suitable frame or casing A, ismounted upon a base consisting of longitudinal sills a and cross sillsb, the said frame having base flanges c by which it may be boltedsecurely to the base, and having in its upper portion a feed hopper B,of usual form and construction.

Between the base flanges c and other flanges d on the sides of the frameand joined by transverse tie plates 6, are formed openings or guides O,by which the boxes of the roller shafts are mounted. These boxes D, Dare made preferably of two sections f and g, bolted together and havesemi-circular hubs or bearings h for the journals E and F of the shaftsof the rollers E and F while within the openings or guides O, and placedabout midway between the boxes are castings I, having upper and lowerflanges or plates 2' extending therefrom and adapted to be fittedbetween the flanges c and dto which they are securely bolted. Thejournal boxes D are fixed rigidly in position by means of bolts 10Serial No. 469,139. (No model.)

passing through the flanges c and d of the frame or casing, while theother boxes D are adjustable along the guides or openings C for thepurpose of adjusting the rolls to compensate for wear of their grindingsurfaces.

The construction of the boxes D and the mechanism by which they areadjusted are clearly shown in Fig. 2, wherein the outer face of theinner section of the box is shown as hearing closely against stops 2formed by the extended ends of the flangest'ot the cast ing interposedbetween the boxes.

A pillar block or casting K bolted between the sills a and b at the endof the machine nearest the adjustable box D is adapted to furnish a seatfor a strong spring L, the inner end of which presses against theadjacent end of the box D or against a wear plate interposed between thetwo. The pillar block or casting also has a bearing m, in which a screwn is mounted with its inner end adapted to bear upon the outer end ofthe spring to compress said spring and thereby hold the journal box witha yielding tension or pressure against the stops formed by the castingI.

In machines of this class, especially when such machines are used forgrinding clay, failings and like material, I have found it desirablevtokeep the grinding surfaces of the rolls normally out of direct contact,or in other words they should be separated slightly so that the Weightof the opposing rolls may be reduced to a minimum. It is also verydesirable that one of the rolls should be so mounted that it may yieldwith its bearings to permit a hard and incompressible object to readilypass between the rolls without unduly straining the roller shafts orbearings. To provide for these desirable results I use the rear ends ofthe flanges i, on the casting I, as stops to limit the inward adjustmentof the roll E and thereby prevent the periphery of this roll fromcontacting with the like surface of the roll opposing it.

This simple construction affords a positive and secure means formaintaining the rolls in proper relation to each other, and when thegrinding surfaces of the rolls wear so as to necessitate the setting upof the roll E, it may be accomplished by cutting awaya portion of thesurfaces of the stops 2, or, in other words, shortening the length ofthe forwardly extending fianges'i of the casting I, thereby permittingthe springs in front of the journal boxes D to force the rear faces ofthe boxes closely against the stops and until the desired distancebetween the working faces of the rolls is attained.

The second desirable object before mentioned is accomplished by means ofthe springs L bearing upon the fronts of the boxes D and the adjustingscrews bearing against the springs, whereby any desired tension may begiven the springs to hold the roll D under suitable pressure, whichtension and pressure maybe regulated by adjusting the screws 7 and whenonce obtained may be maintained by means of a nut or other well knownmeans.

The second part of my invention relates to the means for feeding thematerial to the rolls, and to the devices which I use for this purpose Iwill now refer. Upon the rear end of the machine suitable standards Mare bolted and furnish a support and bearing for a shaft N,which extendstransversely across the machine and is formed or provided witheccentrics N encircled by straps or collars from which bars 0 projectand enter the interior of the hopper.

Upon the frame of the machine suitable clips P are pivotally mounted andhave split or bifurcated portions to receive the lower ends of springplates Q, the upper ends of which are likewise secured by other clips Pand both ends of the springs are secured to the respective clips bymeans of bolts and nuts 0. The upper clips P are secured on short shaftsor pintles R cast with or secured on the under rear end of an inclinedfeedboard or table S, mounted at an incline within the hopper and havingmounted in the under side of its forward end a transverse shaft Sv whoseends project through slots in the side walls of the hopper and areprovided with clips T similar to those before mentioned. These clips Treceive the lower ends of spring plates U located on the outside of thehopper and whose upper ends are bolted to lugs or castings p on theupper portion of the hopper as shown in Fig. 2, while to the shafts Swhich carries the clips T, the forward lower ends of the bars 0 aresuitably connected. From this construction and arrangement of parts itis manifest the feed board is carried by spring or elastic supports andis connected with the eccentrics upon the shaft N so that it may bevibrated back and forth. This feed-board has a width about equal to thewidth of the hopper from one inner side wall to the other; it is set atan incline, and its upper face is grooved or corrugated in form similarto the teeth of a saw to more efiectually feed the material toward itslower end as the board or table is vibrated.

Through the front wall of the hopper is let an inclined gate V whichextends entirely across the interior of the hopper and has its lower endcontiguous to the lower inner end of the vibrating table or board, thesaid gate having pintles r passing through elongated slots .9 in thesides of the hopper casing and engaged by nuts 25 whereby the gate maybe adjusted to increase or decrease the feed outlet between thecontiguous ends of the gate and vibrating board or table, to cause thematerial to be fed to the underlying rolls in a long thin sheet to bethoroughly ground.

In grinding clay or other materials containing more or less moisture,the material will sometimes adhere to the surfaces of the rolls, and toprevent this and always keep the grinding surfaces clean, I employsuitable scrapers shown in Fig. 2. These scrapers are thin wide bladesto extending across the machine and are mounted at a slight incline inpockets or grooves 20 formed in castings IV bolted to the inner sides ofthe base sills of the machine as shown, and the blades or scrapers areadjustable to compensate for wear by means of screws :0 or equivalentmeans. 7

Except as before explained the operation of the machine is similar tothose of a like construction now in use.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is

1. In a grinding mill having rolls between which the material is fed, amechanism for adjusting one of said rolls toward and from the opposingroll, comprising movable journal boxes for the shaft of one of therolls, springs and adjusting screws for forcing the boxes inward wherebythe movable roll is adjusted toward and from the companion roll, andstops consisting of castings placed within the sides of the framebetween the journal boxes having extended ends for limiting the inwardmovement of the movable boxes to prevent the grinding surfaces of therolls coming into direct contact.

2. In a grinding mill, the combination of a frame or casing, a grindingroll havingits shaft mounted in stationary boxes therein, a secondgrinding roll opposing the first named roll, boxes slidably mounted inthe frame and receiving the shaft of the second roll, springs bearingupon said slidable boxes and holding them and their roll under ayielding tension, screws bearing against and regulating the tension ofthe springs, and stops on the frame of the machine for limiting theinward move ment of the boxes to prevent the faces of the opposing rollscoming into contact, said stops having extended ends adapted to be cutaway to compensate for the wear of' the opposing rolls.

3. The combination of the frame with its flanges or plates 0 and (Zseparated from each other to form openings or guides along the sides ofthe machine, journal boxes fixed in said open sides and receiving theshaft of one of the grinding rolls, other journal boxes mounted to slidein said open sides and receiving the shaft of the opposing grindingroll, means for adjusting the slidalole boxes toward the fixed ones, andcastings fixed in said open sides having plates extending along thesides of the machine and forming stops for limiting the inwardadjustment of the slidable boxes.

at. In a grinding mill, the frame, the grinding rolls, the standardsarising from said frame, a transverse shaft mounted therein havingeccentrics, the bars or rods extending from the eccentrics, thepivotally mounted clips P, the feed board having pintles at its upperend, and a shaft at its lower end extending through slots in the frame,clips '1 upon the extended ends of said shaft, and other clips Ppivotally mounted on said pintles, the spring plates connecting theclips P and P and spring plates connecting the clips 20 JOHN THOMPSON.

Witnesses:

T. W. FOWLER, CHAPMAN FOWLER.

